With a population of just 35,000, ALAJUELA is nonetheless Costa Rica's second city. Though it was founded back in 1657, at first sight there's little to distinguish it from San José, at least until the pleasant realization dawns that walking down the street you can smell bougainvillea rather than diesel. The city's few attractions, such as they are, are all less than a minute's walk from the Parque Central. Most impressive is the sturdy-looking whitewashed former jail that houses the Juan Santamaría Cultural-Historical Museum , Av 3, C 0/2 (Tues-Sun 10am-6pm; free), dedicated to Alajuela's most cherished historical figure, the drummer-boy-cum-martyr Juan Santamaría, who sacrificed his life to save the country from the American adventurer William Walker during the battle of 1856. The museum's curiously monastic atmosphere is almost more interesting than the small collection itself, which runs the gamut from mid-nineteenth-century maps of Costa Rica to crumbly portraits of figures involved in the battle of 1856.